We don’t want to get in the middle of any fiercely debated topic. With Whiz, without, we’ll gladly eat a cheesesteak any ol’ way. There’s something about the way the onions char and the steak remains tender even though it’s so thin. Adding Sopressata is just another way to flavor-bomb an already delicious belly-bomb. We’ve got nothing but brotherly love for the Volpi cheesesteak.
Heat griddle over 2 burners over medium-high heat. Add half of the oil to the griddle. Spread the onions on half of the griddle. Season with salt and pepper and cook, stirring occasionally, until golden and softened, 8 to 10 minutes.
Combine beef, Spicy Sopressata, and remaining oil in a bowl and sprinkle with salt and pepper. Add to the griddle in a single layer and cook, tossing occasionally until the meat is just barely pink, 2 to 4 minutes. Mix the onions into the meat and then divide into 4 piles. Arrange 2 slices of cheese over each pile and let cheese start to melt. Using a long metal spatula, scoop each pile into a roll and serve immediately (before it gets soggy).
The easiest way to get your steak as thinly sliced as a cheesesteak needs to be is to ask your butcher ahead of time. Korean markets are also a good source of thin pre-sliced beef. Lacking those options, freeze your steak for an hour or two until the meat is very firm and then slice as thinly as possible with a sharp knife.